DTC Advanced Diagnostics: P1898
DTC P1898:CVT Drive Pulley Pressure Control Valve Stuck ON or CVT Driven Pulley Pressure Control Valve Stuck OFF

General Description

The CVT drive pulley pressure control solenoid valve and the CVT driven pulley pressure control solenoid valve control hydraulic pressure. The CVT drive pulley pressure control solenoid valve and the CVT driven pulley pressure control solenoid valve is controlled by duty cycle output. The spool in the CVT drive pulley pressure control solenoid valve and the CVT driven pulley pressure control solenoid valve moves the valve according to the current, and produces hydraulic pressure in proportion to the current. The powertrain control module (PCM) measures the current that passes through the CVT drive pulley pressure control solenoid valve and the CVT driven pulley pressure control solenoid valve and uses feedback control to compensate for the difference between the measured current and the commanded one. To shift the transmission properly, the PCM outputs a drive/driven pulley oil pressure control signal. If the pulley ratio is out of specified range from the vehicle stopped with the forward clutch engaged to the vehicle running, the PCM detects a CVT drive pulley pressure control solenoid valve stuck ON failure or a CVT driven pulley pressure control solenoid valve stuck OFF and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
Depending on the driving conditions
DTC Type
Two drive cycles, MIL on, Shift position indicator blinks

Enable Conditions
Condition
Minimum
Maximum
Engine speed
[ENGINE SPEED]
500 rpm
–
Vehicle speed
[VEHICLE SPEED]
–
3 mph (5 km/h)*
9 mph (13 km/h)**
–
Accelerator pedal position
2.7 °
–
Shift lever position/mode
D
*: Symptom 1

**: Symptom 2

[ ]: HDS Parameter

Malfunction Threshold
One of these symptoms occurs:

Symptom
Vehicle conditions
PCM detection
1
Stopped with forward clutch engaged
Pulley ratio is more than 2, or less than 3 for at least 400 milliseconds
2
Running
Pulley ratio is more than 1.8, or less than 3

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
CVT drive pulley pressure control solenoid valve stuck on
CVT driven pulley pressure control solenoid valve stuck off

Confirmation Procedure
Operating Condition

1.
Start the engine.
2.
.Accelerate the vehicle in D position/mode until the speed reaches 38 mph (60 km/h).
3.
Slow down and stop the vehicle.
4.
Accelerate the vehicle with wide open throttle.
5.
Slow down and stop the vehicle, and turn the vehicle to the OFF (LOCK) mode.
6.
Repeat Driving Pattern steps 1 through 4.
Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
With the HDS
None.

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on, the shift position indicator blinks, and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.